Cellular Core Armor Plate

ABSTRACT

Armor plate is formed of a cellular substrate surrounded by alternating layers of fabric substrates and metallic substrates and contained in a box. The cellular substrate defines cells containing energy absorbing granular material and/or a shear thickening fluid, and the cells may be oriented perpendicular or parallel to the plane of the armor plate. Fabric substrates may be formed of woven para-aramid yarns and infused with shear thickening fluid, and the metallic substrates may be formed of titanium. The box may be formed of graphite epoxy composite or fiber glass reinforced resin. Armor plate according to the invention may be bolted in the field and fitted to vehicles, aircraft and naval vessels.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims benefit of priority to Provisional Patent Application No. 61/671,387, filed Jul. 13, 2012 and hereby incorporated by reference.

FIELD OF THE INVENTION

This invention relates to an armor plate invention used to protect vehicles and personnel from the effects of blast, projectiles and shrapnel.

BACKGROUND

Protection of land vehicles, aircraft, naval vessels, as well as personnel against the effects of blast, projectiles and shrapnel through the use of armor plate involves a tradeoff between the competing requirements of mobility and effectiveness. This tradeoff is especially apparent in the case of traditional armor plate, such as rolled homogenous steel or other metals, wherein both the weight and the degree of protection increase with the thickness of the plate, thereby imposing practical limits on the degree of protection afforded at the expense of mobility due to the increase in weight of the armor.

In this time of asymmetrical warfare, where battles are fought without a clear demarcation of a front line, it has further become apparent that only some of the heaviest main battle tanks are sufficiently armored to withstand the effects of improvised explosive devices (IEDs) and underground mines encountered on the modern battlefield. So called “thin skinned” vehicles, such as armored cars, trucks, and high mobility multipurpose wheeled vehicles (HMMWVs) suffer grievous losses when subjected to the effects of the IED, mines or projectiles such as the ubiquitous rocket propelled grenade. Designed and built with an emphasis on mobility, large numbers of thin skinned vehicles in the military inventory lack the armor protection necessary for crew survivability.

There is clearly a need for armor which will provide effective protection against blast, shock waves, projectiles and shrapnel without unduly compromising the mobility of the vehicle, aircraft, ship or person wearing the armor. There is furthermore a need for armor which can be readily applied in the field as needed for thin skinned vehicles, aircraft or ships otherwise lacking such protection.

SUMMARY

The invention concerns an armor plate invention which may be used to protect vehicles and personnel from the effects of blast, projectiles and shrapnel. In one example embodiment, the invention comprises a first cellular substrate defining a plurality of cells arranged adjacent to one another. The first cellular substrate has first and second faces oppositely disposed from one another. A granular material is positioned within at least some of the cells. A first fabric substrate is attached to the first face of the first cellular substrate in overlying relation, and a second fabric substrate is attached to the second face of the first cellular substrate in overlying relation. A first metallic substrate is attached to the first fabric substrate in overlying relation and a second metallic substrate is attached to the second fabric substrate in overlying relation.

In one example embodiment, the granular material comprises S2 glass. Alternately or in addition, the granular material may comprise graphite particles. A shear thickening fluid may also be contained within at least some of the cells. The first and second fabric substrates may comprise for example, woven para-aramid yarns sold under the trademark Kevlar. The first and second fabric substrates may be infused with a shear thickening fluid.

In a particular example of the invention, the first and second metallic substrates may comprise titanium.

The example embodiment may further comprise a first panel attached to the first metallic substrate, a second panel attached to the second metallic substrate, and a plurality of side panels attached to the first and second panels. The side panels surround the first cellular substrate.

In another example embodiment, the armor plate described above may further comprise a third fabric substrate attached to the first metallic substrate in overlying relation and a fourth fabric substrate attached to the second metallic substrate in overlying relation. The third and fourth fabric substrates may also comprise woven para-aramid yarns. The third and fourth fabric substrates may also be infused with a shear thickening fluid.

The armor plate having the third and fourth fabric substrates noted above may also include a first panel attached to the third fabric substrate and a second panel attached to the fourth fabric substrate as well as a plurality of side panels attached to the first and second panels. The side panels surround the first cellular substrate.

In yet another embodiment, the armor plate may further comprise a third metallic substrate attached to the third fabric substrate in overlying relation and a fourth metallic substrate attached to the fourth fabric substrate in overlying relation. In this example embodiment the third and fourth metallic substrates may comprise titanium.

The example armor plate may further comprise a fifth fabric substrate attached to the third metallic substrate in overlying relation and a sixth fabric substrate attached to the fourth metallic substrate in overlying relation. The fifth and sixth fabric substrates may comprise woven para-aramid yarns. The fifth and sixth fabric substrates may also be infused with a shear thickening fluid.

In another alternate embodiment, an example armor plate according to the invention may further comprise a first panel attached to the fifth fabric substrate, a second panel attached to the sixth fabric substrate, and a plurality of side panels attached to the first and second panels. The side panels surround the first cellular substrate.

In a particular example of the invention, each one of the cells has a first and a second end oppositely disposed. The first ends of the first cells are attached to the first fabric substrate. The second ends of the cells are attached to the second fabric substrate. The granular material is captured within at least some of the cells between the first and second fabric substrates.

In another example embodiment, the armor plate may comprise a first side having a first side panel positioned between the first and second fabric substrates, and a second side arranged opposite to the first side and having a second side panel positioned between the first and second substrates. In this example each one of the cells has a first and a second end oppositely disposed. The first ends of the first cells are attached to the first side panel, and the second ends of the cells are attached to the second side panel. The granular material is captured within at least some of the cells between the first and second side panels.

In another example embodiment, the armor plate comprises a first cellular substrate defining a plurality of cells arranged adjacent to one another. The first cellular substrate has first and second faces oppositely disposed from one another. A granular material is positioned within at least some of the cells. A first fabric substrate is attached to the first face of the first cellular substrate in overlying relation. A second fabric substrate is attached to the second face of the first cellular substrate in overlying relation. A first metallic substrate is attached to the first fabric substrate in overlying relation. A second metallic substrate is attached to the second fabric substrate in overlying relation. A third fabric substrate is attached to the first metallic substrate in overlying relation. A fourth fabric substrate is attached to the second metallic substrate in overlying relation. A first panel is attached to the third fabric substrate. A second panel is attached to the fourth fabric substrate. A plurality of side panels are attached to the first and second panels and surround the first cellular substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an isometric, partial sectional view of an example cellular core armor plate;

FIG. 2 is an isometric, partial sectional view of an example cellular core armor plate;

FIG. 3 is an isometric, partial sectional view of an example cellular core armor plate;

FIG. 4 is an isometric, partial sectional view of an example cellular core armor plate;

FIG. 5 shows a military vehicle using cellular core armor plate as applique' armor;

FIG. 6 shows an aircraft using cellular core armor plate as applique' armor; and

FIG. 7 shows a naval vessel with cellular core armor plate on its hull and superstructure.

DETAILED DESCRIPTION

FIG. 1 shows, in partial sectional view, an example cellular core armor plate 10 according to the invention. The use of the term “armor plate” herein refers to the entire invention. Armor plate 10 comprises a cellular substrate 12 which defines a plurality of cells 14 arranged adjacent to one another. In this example, cells 14 are square in cross section, formed by an “egg crate” construction of mutual sidewalls perpendicularly oriented relative to one another. Cells 14 could also have the hexagonal cross section of a traditional honeycomb core. The cells 14 may also be coated with rubber or other pliant, resilient damping material. Cells 14 contain a granular material 16, for example S2 glass nodules or graphite particles. All or some of the cells may contain the granular material, and the cells may be completely or partially filled with the granular material. Alternately or in addition to the granular material, the cells may contain a dilatant 18, for example, a shear thickening fluid in which the viscosity increases in proportion to the rate of shear strain on the fluid.

Cellular substrate 12 has oppositely disposed faces 20 and 22 to which are attached fabric substrates 24 and 26. The fabric substrates are attached to the cellular substrate in overlying relation. Attachment may be through adhesive bonding or belting to an outer composite case described below. It is advantageous to form the fabric substrates 24 and 26 from woven synthetic para-aramid yarns, which provide excellent resistance to penetration by projectiles and shrapnel. The fabric substrates may be infused with a dilatant 28, for example, a shear thickening fluid, to improve their ballistic characteristics. Metallic substrates 30 and 32 are attached, respectively, to the fabric substrates 24 and 26. The metallic substrates are attached to the fabric substrates in overlying relation, and attachment may be effected through adhesive bonding. It is advantageous to form the metallic substrates from titanium in view of its excellent strength to weight ratio. Additional layers of fabric substrates 34 and 36 are respectively attached to the metallic substrates 30 and 32. Again, these fabric substrates 34 and 36 are advantageously formed of woven synthetic para-aramid yarns, and the fabric may be infused with a dilatant 28, such as a shear thickening fluid. In addition, the para-armid yarns may be interwoven with other elements such as metallic wires, graphite filaments and glass fiber.

The assembly comprising the cellular substrate 12, the fabric substrates 24, 26, 34 and 36 along with the metallic substrates 30 and 32 is advantageously contained within a box 38. Box 38 comprises oppositely disposed face panels 40 and 42 attached, respectively, to the fabric substrates 34 and 36. The face panels 40 and 42 are attached to the fabric substrates 34 and 36 in overlying relation, and attachment may be effected by adhesive bonding. Box 38 further comprises a plurality of side panels 44, 46, 48 and 50 which are positioned between the face panels 40 and 42 and close off the cellular substrate 12. Note that the side panels may have a channel shaped cross section, imparting stiffness to the armor plate 10. The side panels may be attached directly to the face panels 40 and 42, or they may be attached to the fabric substrates 22 and 24 as shown in the figures. The substrates may further be enclosed in a ballistic bag strapped securely within the box 38. The face panels 40 and 42 and the side panels 44, 46, 48 and 50 may be formed from graphite composite material for a high strength and light weight structure. Alternately, box 38 may be formed of a glass reinforced resin such as fiberglass. It may also be advantageous to attach at least one of the face panels to a side panel with a hinge to permit the box 38 to be opened for ease of mounting in the field. For example, face panel 40 could be hingedly attached to side panel 48, and a locking mechanism can be positioned on side panel 44 to secure the face panel 40 in place.

In the example armor plate embodiment 10 shown in FIG. 1, cells 14 have oppositely disposed ends 52 and 54. The cells are oriented parallel to the plane 56 of the armor plate 10 so that their ends 52 and 54 are attached, respectively, to the oppositely arranged side panels 44 and 48 comprising box 38. In this configuration the side panels seal off the cells and capture their contents, for example, granular material 16 and/or the dilatant 18 permitting them to exit safely from the sides of the vehicle. By orienting the cells 14 parallel to the plane 56 of the plate 10 it is expected that the plate will be more effective in absorbing and redirecting the blast of an explosion, as the compressive force from the shock wave will tend to crush the cells 14 and force the fragments and the granular material 16 and/or the dilatant 18 out through the side panels 44 and 48 to which they are attached. Side panels 44 and 48 may be made thinner than side panels 46 and 50 to more readily accommodate the blow-out of the cell contents and facilitate redirecting of the blast away from the vehicle. When mounted on the underside of a vehicle for example, it is advantageous to orient the armor plate 10 so that the blast and fragments are directed to the left and right sides of the vehicle, thereby preventing upward damaging travel of fragments and shockwaves.

In an alternate armor plate embodiment 58, shown in FIG. 2, the cells 14 of the cellular substrate 12 are oriented perpendicular to the plane 56 of the plate 58. In this configuration the ends 52 and 54 of the cells 14 form faces 20 and 22 and are attached to the fabric substrates 24 and 26, which capture the cell contents (granular material 16 and/or dilatant 18) within each cell. The perpendicular orientation of the cells 14 provides increased resistance to crushing under the compressive shock of an explosion. It is thus expected that the mitigation of the blast will depend on the change in the nature of the substrates forming the armor plate 58 as the shock wave propagates through the solid metallic and fabric layers to the open cellular layer, containing energy absorbing granular material 16 and/or dilatant 18. Except for the orientation of the cells 14 of the cellular substrate 12, armor plate embodiment 58 is substantially the same as armor plate 10 with respect to the fabric and metal substrates, and therefore the configuration need not be described again in detail.

FIG. 3 shows a further armor plate embodiment 60, which differs from armor plate 10 in that there are additional layers of metallic substrates 62 and 64 and fabric substrates 66 and 68. Additional metallic substrates 62 and 64 are attached, respectively, to fabric substrates 34 and 36, and additional fabric substrates 66 and 68 are attached respectively to metallic substrates 62 and 64 as well as to the face panels 40 and 42. The additional fabric and metallic substrates are expected to provide increased protection with only a modest increase in weight. Fabric substrates 66 and 68 are advantageously formed of woven synthetic para-aramid yarns, and the metallic substrates are advantageously formed of titanium. Similarly, FIG. 4 depicts yet another armor plate embodiment 70, which differs from armor plate 58 in that there are additional layers of metallic substrates 62 and 64 and fabric substrates 66 and 68. Additional metallic substrates 62 and 64 are attached, respectively, to fabric substrates 34 and 36, and additional fabric substrates 66 and 68 are attached respectively to metallic substrates 62 and 64 as well as to the face panels 40 and 42. The additional fabric and metallic substrates are expected to provide increased protection with only a modest increase in weight. Fabric substrates 66 and 68 are advantageously formed of woven synthetic para-aramid yarns, and the metallic substrates are advantageously formed of titanium.

Although the armor plate embodiments depicted herein are symmetric about the cellular substrate 12 with respect to the fabric and metallic layers, it is understood that the invention also encompasses asymmetrical armor plate, for example, plate comprising fewer fabric and/or metallic layers on one side of the cellular substrate than on the opposite side.

In a practical example of cellular core armor plate according to the invention, the cellular substrate 12 may be formed of aluminum or titanium foil with a thickness between about 0.0020 inches to about 0.0050 inches. Foil thicknesses as great as ⅛ inch are also feasible. Graphite composites are also feasible. Cell sizes may range between about 0.125 inches and about 1 inch on a side, with cells of about 0.25 inches per side expected to be advantageous. When the cellular substrate is oriented perpendicular to the plane 56 of the plate (as shown in FIGS. 2 and 4), the height of the cells (the distance from end 52 to end 54) may be between about 1 inch and about 4 inches. Similarly, the thickness of the cellular substrate 12 is between about 1 inch and about 4 inches when the cellular substrate is oriented parallel to the plane 56 of the plate (as shown in FIGS. 1 and 3). Cellular substrates are commercially available from many suppliers, for example, Benecor Inc. of Wichita, Kans.

The fabric substrates 24, 26, 34 , 36, 66 and 68 may comprise commercially available blankets, such as those supplied by Barraday Inc. of Cambridge, Ontario. Of particular note are blankets formed of 7 layers of Kevlar brand para-aramid yarns, which may also be infused with a shear thickening agent, such as silica particles in a polyethylene glycol carrier fluid. In addition, granular particles or fibers, such as graphite or glass may also be included in the shear thickening agent.

As noted the metallic substrates 30, 32, 62 and 64 are advantageously formed from titanium, specifically 0.125 inch thick ATI 425 mil spec plate. The face panels 40 and 42 and the various side panels 44, 46, 48 and 50 forming the box 38 may be made of graphite epoxy or fiberglass composites. In general, thicknesses of about 0.25 inches are expected to provide a light weight, robust design, however, it may be advantageous to make the side panels 44 and 48 0.03125 inches thick to direct the blow-out of the granular material and/or the shear thickening fluid and the fragments along the long axis of the cells 14 when they are oriented parallel to the plane of the plate. Adhesive bonding of the various substrate layers to one another may be effected using epoxy adhesives.

The cellular core armor plate according to the invention may have an overall thickness of about 4 to 5 inches and may be manufactured in rectangular pieces 1 foot by 1 foot square, 2 feet by 2 feet square, or 2 feet by 4 feet to provide but a few practical examples. Smaller or larger sizes are of course feasible, as dictated by the use of the armor plate.

FIGS. 5-7 illustrate a few potential uses of the cellular core armor plate. FIG. 5 shows a thin skinned military vehicle 72 “up-armored” through the use of cellular core armor plates 10 used as applique' armor on the sides and bottom of the vehicle where mine damage and small arms fire can be expected. Similarly, areas on aircraft 74 vulnerable to ground fire, such as the underbelly, may be covered with cellular core armor plates 10 for increased protection. Naval vessels 76, especially those designed for riverine and littoral combat, where small arms fire is encountered, can benefit from the increased protection afforded to hull and superstructure by cellular core armor plates 10. It is also expected that cellular core armor plates according to the invention may be worn by soldiers within ballistic vests due to the light weight of the construction. Due to its simple, robust and light weight construction, it is expected that cellular core armor plate will be readily and quickly installable in the field, without the need for special tools, equipment or processes. The armor plate according to the invention may be bolted directly to the vehicle, aircraft or vessel as needed, or installed using brackets which permit easy removal and replacement of spent armor plate. Armor plate may also be recovered for reuse on other vehicles. Cellular core armor plates may also be layered one atop the other in a “piggyback” configuration for increased armor protection provided that adequate ground clearance is maintained, for example 7-8 inches. Additionally, cellular core armor plate according to the invention may also be installed on vehicles as a single large unit by the manufacturer.

Cellular core armor plate according to the invention is expected to provide increased protection from blast, shockwaves, projectiles and shrapnel without sacrifice of mobility due to its light weight, ability to attenuate shock, and resistance to penetration and at a reduced weight and cost in comparison with other methods of protection. 

What is claimed is:
 1. Armor plate, comprising: a cellular substrate defining a plurality of cells arranged adjacent to one another, said cellular substrate having first and second faces oppositely disposed from one another; a granular material positioned within at least some of said cells; a first fabric substrate attached to said first face of said cellular substrate in overlying relation; a second fabric substrate attached to said second face of said cellular substrate in overlying relation; a first metallic substrate attached to said first fabric substrate in overlying relation; a second metallic substrate attached to said second fabric substrate in overlying relation.
 2. The armor plate according to claim 1, wherein said granular material is selected from the group consisting of S2 glass, graphite, and combinations thereof.
 3. The armor plate according to claim 1, further comprising a shear thickening fluid contained within at least some of said cells.
 4. The armor plate according to claim 1, wherein said first and second fabric substrates comprise woven para-aramid yarns.
 5. The armor plate according to claim 1, wherein said first and second fabric substrates are infused with a shear thickening fluid.
 6. The armor plate according to claim 1, wherein said first and second metallic substrates comprise titanium.
 7. The armor plate according to claim 1, further comprising: a first panel attached to said first metallic substrate; a second panel attached to said second metallic substrate; and a plurality of side panels attached to said first and second panels and surrounding said cellular substrate.
 8. The armor plate according to claim 1, further comprising: a third fabric substrate attached to said first metallic substrate in overlying relation; a fourth fabric substrate attached to said second metallic substrate in overlying relation.
 9. The armor plate according to claim 8, wherein said third and fourth fabric substrates comprise woven para-aramid yarns.
 10. The armor plate according to claim 8, wherein said third and fourth fabric substrates are infused with a shear thickening fluid.
 11. The armor plate according to claim 8, further comprising: a first panel attached to said third fabric substrate; a second panel attached to said fourth fabric substrate; and a plurality of side panels attached to said first and second panels and surrounding said cellular substrate.
 12. The armor plate according to claim 8, further comprising: a third metallic substrate attached to said third fabric substrate in overlying relation; a fourth metallic substrate attached to said fourth fabric substrate in overlying relation.
 13. The armor plate according to claim 12, wherein said third and fourth metallic substrates comprise titanium.
 14. The armor plate according to claim 12, further comprising: a fifth fabric substrate attached to said third metallic substrate in overlying relation; a sixth fabric substrate attached to said fourth metallic substrate in overlying relation.
 15. The armor plate according to claim 14, wherein said fifth and sixth fabric substrates comprise woven para-aramid yarns.
 16. The armor plate according to claim 14, wherein said fifth and sixth fabric substrates are infused with a shear thickening fluid.
 17. The armor plate according to claim 14, further comprising: a first panel attached to said fifth fabric substrate; a second panel attached to said sixth fabric substrate; and a plurality of side panels attached to said first and second panels and surrounding said first cellular substrate.
 18. The armor plate according to claim 1, wherein each one of said cells has a first and a second end oppositely disposed, said first ends of said first cells being attached to said first fabric substrate, said second ends of said cells being attached to said second fabric substrate, said granular material being captured within said at least some of said cells between said first and second fabric substrates.
 19. The armor plate according to claim 1, further comprising: a first side having a first side panel positioned between said first and second fabric substrates; a second side arranged opposite to said first side and having a second side panel positioned between said first and second substrates; and wherein each one of said cells has a first and a second end oppositely disposed, said first ends of said first cells being attached to said first side panel, said second ends of said cells being attached to said second side panel, said granular material being captured within said at least some of said cells between said first and second side panels.
 20. Armor plate, comprising: a cellular substrate defining a plurality of cells arranged adjacent to one another, said cellular substrate having first and second faces oppositely disposed from one another; a granular material positioned within at least some of said cells; a first fabric substrate attached to said first face of said cellular substrate in overlying relation; a second fabric substrate attached to said second face of said cellular substrate in overlying relation; a first metallic substrate attached to said first fabric substrate in overlying relation; a second metallic substrate attached to said second fabric substrate in overlying relation; a third fabric substrate attached to said first metallic substrate in overlying relation; a fourth fabric substrate attached to said second metallic substrate in overlying relation; a first panel attached to said third fabric substrate; a second panel attached to said fourth fabric substrate; and a plurality of side panels attached to said first and second panels and surrounding said first cellular substrate. 